Field of the Invention
The invention relates to a recognition apparatus, and more particularly, relates to a speech recognition apparatus and a speech recognition method.
Description of Related Art
In general, hearing-impaired people can clearly hear voice signals with low frequency but have trouble receiving voice signals with higher frequency (e.g., a consonant signal). In conventional determination method for the consonant signal, a signal processing is performed in a frequency domain by using the determination method mainly including a non real-time determination for the consonant signal and a real-time determination for the consonant signal. The non real-time determination for the consonant signal performs the determination mainly by using an energy and a zero-cross rate. The real-time determination for the consonant signal mainly determines whether the voice signal is the consonant signal according to whether a ratio of a high frequency signal to a total energy is greater than a fixed value and whether a ratio of a low frequency signal to the total energy is less than the fixed value. Although the conventional determination method for the consonant signal is capable of distinguishing the consonant signal and a noise signal, yet an accuracy of said method still fails to meet the actual demand.